#include <stdio.h>

#define SIZE 10

int sump(int *start, int *end);

int main(void)
{
    int marbles[SIZE] = {20, 10, 5, 39, 4, 16, 19, 26, 31, 20};
    long answer = sump(marbles, marbles + SIZE);
    printf("The total number of marbles is %ld.\n", answer);
    return 0;
}

/* 使用指针算法 */
int sump(int *start, int *end)
{
    int total = 0;
    while (start < end)
    {
        total += *start; // 把数组元素的值加起来
        start++; // 让指针指向下一个元素
    }
    return total;
}
